Goss Moor National Nature Reserve, Cornwall · environmental assessment for the Goss Moor National...

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Goss Moor National Nature Reserve, Cornwall Palaeo- environmental Assessment Oxford Archaeology North February 2012 Natural England OA Job No: L10407 Issue No: 2011/2012 1271 NGR: SW 95420 60136

Transcript of Goss Moor National Nature Reserve, Cornwall · environmental assessment for the Goss Moor National...

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Goss MoorNational NatureReserve,Cornwall

Palaeo-environmentalAssessment

Oxford Archaeology North

February 2012

Natural England

OA Job No: L10407Issue No: 2011/2012 1271NGR: SW 95420 60136

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Goss Moor National Nature Reserve, Cornwall: Palaeo-environmental Assessment Report 1

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CONTENTS

SUMMARY ................................................................................................................ 2

ACKNOWLEDGEMENTS ............................................................................................ 3

1. INTRODUCTION ................................................................................................ 41.1 Circumstances of the Project ......................................................................... 41.2 Site Background ........................................................................................... 41.3 Archive......................................................................................................... 5

2. PLANT REMAINS ............................................................................................... 62.1 Assessment of the Plant Macrofossils............................................................ 6

3. INSECT REMAINS .............................................................................................. 83.1 Assessment of the Insect Remains................................................................. 8

4. POLLEN .......................................................................................................... 104.1 An Assessment of the Pollen....................................................................... 10

5. DIATOMS AND PHYTOLITHS ........................................................................... 145.1 Diatoms and Phytoliths ............................................................................... 14

6. DISCUSSION.................................................................................................... 166.1 Conclusions ................................................................................................ 16

BIBLIOGRAPHY ...................................................................................................... 18

APPENDIX 1: TABLES............................................................................................ 20

APPENDIX 2: PROJECT DESIGN.............................................................................. 25

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SUMMARY

Natural England undertook two excavations ahead of a project to divert the River Falfrom an over-deepened channel. Eleven environmental bulk samples, including onesample of less than one litre in volume, and one monolith sample were taken duringthe excavation from the western trench (SW 95420 60136). The trench revealed asequence of stratified organic-rich, clay, and gravel deposits. Five of the bulk sampleswere sequential and the remaining six were more general ones from deposits. Thesesamples were submitted to Oxford Archaeology North to be assessed for palaeo-environmental remains.

The eleven bulk samples were processed and assessed for plant and insect remains.The monolith sample was processed and assessed for pollen, fungal spores, diatomsand phytoliths. The results for all the material types are presented in this report.

The assessment of the plant and insect remains indicated that these types of remainshad been poorly preserved in the deposits possibly because of the high level ofhumification. Both pollen and fungal spores were present and suggest that changeswere taking place in the landscape when the deposits were accumulating. The pollenrecorded in the basal pollen sample at a depth of 0.40-0.41m suggested that willowwas growing locally but the pollen in the upper samples suggest that the willow wasreplaced by more open grassland with some stands of hazel and heather scrub andtowards the top of the stratigraphy areas of open water. Diatoms and plant phytolithswere also recorded in the upper samples and support the presence of grasses andsedges with areas of open water.

Recommendations are made for further analysis of the pollen but of no other palaeo-environmental material. This analysis should further refine the possible environmentalchanges suggested by the assessment of a transition from potential willow wetland toopen grassy meadows with heather and hazel scrub environments and then to a moreopen, wet and possibly grazed landscape. It may also be able to confirm theidentification of the cereal-type pollen recorded which could be related to possiblecultivation. These changes may be related to local mining and quarrying activities.

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ACKNOWLEDGEMENTS

OA North would like to thank Natural England for commissioning the palaeo-environmental assessment of the samples from Goss Moor National Nature Reserve,Cornwall (TRURI 2011:19). We would also like to thank the Geography Departmentof the University of Lancaster for use of their laboratories.

The insect remains were processed, assessed and reported on by David Smith and hiscolleagues at Birmingham University. The diatoms and phytoliths samples wereprocessed and assessed by Philip Barker of Lancaster University. The environmentalbulk samples were processed in house by Sandra Bonsall. Sandra and Denise Druceassessed the waterlogged plant remains and Denise wrote the report on the plantremains. The pollen samples were prepared by Sandra and the pollen and fungalspores were assessed by Mairead Rutherford, who wrote the pollen report. Thepalaeo-environmental report was compiled by Elizabeth Huckerby.

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1. INTRODUCTION

1.1 CIRCUMSTANCES OF THE PROJECT

1.1.1 Natural England commissioned Oxford Archaeology North (OA North) toundertake a palaeo-environmental assessment of environmental samples takenduring two excavations ahead of a project to divert the River Fal from an over-deepened channel, which was created in the 1970s to prevent the threat ofpollution episodes from the China Clay industry upstream. The two excavationtrenches were at both ends of this channel.

1.1.2 The lower, western trench exposed a sequence of stratified deposits of mainlygravels and clays with a more organic looking layer towards the base. Thedeposits are thought to have been lain down naturally and are described aspossibly water-lain in a flood plain. A single archaeological feature wasidentified in this trench.

1.1.3 The eastern trench and the deposits are described as being disturbed possiblyas the result of tin-streaming and more recently by gravel extraction. GossMoor was extensively disturbed by tin and gravel extraction in the 19th and20th centuries although this may have commenced in the Bronze Age.

1.1.4 The scope of the assessment was laid out in the paleo-environmentalassessment Project Design (Appendix 1). It included the assessment of theplant remains, the insect remains, pollen, fungal spores and diatoms.

1.1.5 The different environmental material types assessed are reported onindividually. The reports are drawn together in a discussion about the palaeo-environmental assessment for the Goss Moor National Nature Reserve (NNR).

1.2 SITE BACKGROUND

1.2.1 Goss Moor NNR, Cornwall is situated in a broad relatively flat, valley basinwhich forms the headwaters of the River Fal. The following information aboutthe nature reserve has been obtained from the Natural England web site forGoss Moor NNR. The extensive mining of alluvial tin deposits since theBronze Age, and in the more recent past gravel extraction, has resulted in theformation of wetland habitats. No industrial activity has taken place since the1960s.

1.2.2 The vegetation today includes areas of heath on the site, which support heatherand bell heather with bristle bent and purple moor grass, while wetter areassupport lesser butterfly orchid, hemlock water dropwort and the scarce yellowcentaury. More acidic areas are home to bog plants like heath spotted orchid,marsh St John's wort and the scarce marsh clubmoss.

1.2.3 Eleven bulk samples (including one sample that was less than one litre involume) and one monolith sample were taken by Natural England andsubmitted to Oxford Archaeology North for the assessment of plantmacrofossils, insects, and diatoms. The samples came from the western trench

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(SW 95420 60136) dug as part of the project to divert the River Fal. Thetrench revealed a sequence of stratified organic-rich, clay, and gravel deposits.

1.3 ARCHIVE

1.3.1 A full archive of the work undertaken has been produced to a professionalstandard in accordance with current English Heritage guidelines (EnglishHeritage 1991). The archive will be submitted to Natural England.

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2. PLANT REMAINS

2.1 ASSESSMENT OF THE PLANT MACROFOSSILS:

Denise Druce and Sandra Bonsall

2.1.1 Quantification and methodology: This report outlines the results of the plantmacrofossil assessment of the eleven bulk samples, which was carried out by ateam of OA North palaeo-environmental specialists. The samples from thewestern trench revealed a sequence of stratified organic-rich, clay, and graveldeposits. As the deposits are believed to be naturally accumulated and water-lain, there was the potential for the survival of plant remains by waterlogging.Plant remains are good indicators of the local flora and can be used as proxyindicators of climate change and hydrological conditions (Barber and Charman2003).

2.1.2 The bulk samples came from the stratigraphic units visible in the westerntrench, and include five 0.05-0.08m thick series samples (samples 3-4), asingle 0.01m sample, and two ‘bulk’ samples were taken from an organic‘peat’ deposit revealed towards the base of the trench. Two bulk samples camefrom the overlying black gravel (sample 2) and brown humic layer (sample 1)and one bulk sample was taken from the lower fill of a linear feature visible inthe trench.

2.1.3 Ten bulk samples of between six and ten litres in volume and one sampleequal or less than one litre were washed through a 250 micron mesh, retainedwet and examined under a low-powered binocular microscope at up to x40magnification. Any plant remains were provisionally identified and quantifiedon a scale of 1-4, where 1 is rare (<5 items) and 4 is abundant (>100 items).Identification was aided by comparison with the modern reference collectionheld at OA North. The components of the matrix, such as amorphous organicremains, wood, roots, insect remains, stones, and charcoal were alsoquantified. The suitability of the samples for further analysis was also notedand presented in table 1 (Appendix 1). Plant nomenclature follows Stace(2010).

2.1.4 Assessment results: All of the samples described as peat in the field containedabundant organic material, however, high levels of humification meant thatvery little could be identified. The frequent to common wood fragmentsrecorded in the peat samples indicate the presence of a woody environmentduring their accumulation. Rare to frequent seeds preserved throughwaterlogging were recorded in only a few of the samples, and these includeRumex acetosella (sheep’s sorrel), common on cultivated land, grassland andheathy open ground, and Carex sp (sedge), which grows in damp/wetlocations. Most of the samples contained common stones, which are likely toderive from the layers of over/underlying gravel deposits. Rare charcoalfragments were recorded in the ‘peat’ samples, which may come from nearbyburning activity/events.

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2.1.5 Potential: It is obvious from the stratigraphic sequence that hydrologicalchanges took place on Goss Moor, which is manifest in the shift from graveldeposition to peat accumulation, and then back to gravel deposition oncemore. Although the waterlogged seeds recorded in a couple of the sampleswould provide suitable material for radiocarbon dating, their general paucity inthe remaining samples, coupled with high levels of organic humification,means that further study of the plant remains would not add significantly toexisting knowledge. Accordingly, there are no recommendations for furtheranalysis.

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3. INSECT REMAINS

3.1 AN ASSESSMENT OF THE INSECT REMAINS

David Smith

3.1.1 Introduction: ten samples of material were presented for assessment for insectremains from the western trench excavation at Goss Moor NNR. Four samplescome from a sequence of stratified sands, clays, gravels with more organic‘peat’ development towards the base. A single sample came from anassociated trench feature.

3.1.2 This assessment was carried out to establish the following:

• Are insect remains present? And if so, are they of interpretative value?• Do the insect remains from these samples provide information on the

nature of local water conditions?• Do the insect remains provide information on the nature of the surrounding

landscape?

3.1.3 Methodology: The samples were processed using the standard method ofparaffin flotation as outlined by Kenward et al (1980). The weights andvolumes of the individual samples are included in Table 2 (Appendix 1). Insectremains were sorted from the flot and examined under a low-power binocularmicroscope. The system for ‘scanning’ faunas as outlined by Kenward et al.(1985) was initially followed in this assessment. However, since the faunasrecovered were so small it has been possible to identify all taxa that werepresent as far as possible. The nature of the preservation and the potential forarchaeological interpretation is outlined in Table 3.

3.1.4 Results: The insect taxa recovered from the flots are listed in Table 2. Thetaxonomy used for the Coleoptera (beetles) follows that of Lucht (1987). Thenumbers of individual insects present is estimated using the following scale: += 1-2 individuals ++ = 2-5 individuals +++ = 5-10 individuals ++++ = 10+individuals +++++ = 20+ individuals ++++++ = 100s of individuals.

3.1.5 Discussion: The insect faunas recovered were very small, eroded andfragmented suggesting that preservation is poor. Many of the taxa recoveredare not indicative of specific water conditions or landscapes. Unfortunately,this suggests that these insect faunas have a very limited potential forlandscape reconstruction.

3.1.6 Only a few of the taxa recovered are indicative of the nature of thesurrounding landscape. Given the poorly preserved nature of the insect faunasrecovered, and their small size these results should not be over emphasised.Several specimens of the Aphodius ‘dung beetles’ were recovered from allfour samples that produced insect remains. The recovery of these taxaprobably indicate that herbivores, possibly cattle, were grazing in the areasince they are commonly associated with animal dung lying in pasture (Jessop1986). The single individual of the ‘leaf beetle’ Hydrothassa marginella is

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normally associated with marsh marigold and indicates that this species ofplant was present in the area. Similarly, the weevil Orobitis cyaneus isassociated with violets.

3.1.7 Recommendations and Conclusions: There is no need for any furtheridentification of the insect remains from these contexts. Unless other materialfrom this site is recovered, which is clearly better preserved, there seems to beno reason to undertake further archaeological insect work at this location.

3.1.8 If the pollen or the plant macrofossils from this site are published theinformation from the insect remains can be included as additional notes.

Samplenumber

Degree ofpreservation

Comparative size offaunas

Waterconditions

landscape Overallpotential

Top of peat,brown layer

Very fragmentedPoor preservation

moderate/ Small no information Aphodius dung beetle mightsuggest grassland or pasture

Very low

Top of peat,Black/browngravel

Very fragmentedVery poorpreservation

very small no information Single Aphodius dung beetlemay suggest grassland orpasture.

Very low

Top of peatdark gravel

Very fragmentedVery poorpreservation

very small no information Single Aphodius dung beetlemay suggest grassland orpasture.

Very low

Top of peat0.05m

No preservation - - - none

Top of peat,0.06-0.10 m

Very fragmentedVery poorpreservation

very small No information Aphodius dung beetle maysuggest grassland or pasture.

Very low

Peat 0.10 m-0.15 m

Very fragmentedVery poorpreservation

very small No information Aphodius dung beetle maysuggest grassland or pasture.

Very low

Peat 0.15-0.20m

No preservation - - - none

Above gravelpeat 0.20-0.28m

Very fragmentedVery poorpreservation

very small No information Single Aphodius dung beetlemay suggest grassland orpasture.

Very low

Bottom of peat No preservation - - - noneBottom ofFeature

no preservation - - - none

Table 3. Summary of the nature of the insect faunas from Goss Moor NNR,Cornwall

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4. POLLEN

4.1 AN ASSESSMENT OF THE POLLEN

Mairead Rutherford

4.1.1 Five sub-samples from the western trench excavation have been assessed forpollen and non-pollen palynomorphs (NPP) (including fungal spores). Thewestern trench exposed a sequence of stratified deposits of mainly gravels andclays with a more organic layer towards the base. The deposits may representflood-plain water-lain deposits (Natural England, pers comm).

4.1.2 The vegetation history of Dartmoor (Caseldine and Hatton 1996) refers toclearances of woodlands by tinners who used alder woodlands that survived onvalley floors (after upland areas had already been cleared of woodland). Thenature, extent and timing of human settlement and landuse on Bodmin Moorhas been examined by Gearey and Charman (1996) and by Gearey, Charmanand Kent (2000a, 2000b). Mighall and Chambers (1993) described decliningoak (Quercus) and hazel (Corylus) pollen as potential evidence that such woodmay have been used for firesetting and mining operations at copper mines inWales.

4.1.3 Druce (Druce and Verrill forthcoming) recorded pollen data from apalaeochannel deposit near Indian Queens (A30) that suggested a relativelylong period of settlement or farming activity from the early/middle BronzeAge, with a mixed economy of relatively non-intensive pastoralism andpossible small-scale arable cultivation.

4.1.4 Methodology: the monolith was cleaned and the lithology described. Five sub-samples were assessed for pollen from a single monolith representing a totaldeposit thickness of 0.50m. The sub-samples were chosen on the basis ofsuitability of the lithologies; details are presented in the Table 4:

Lithology (m) Sub-samples(m)

0-0.05 Yellow/brown/grey silty clay/ orange mottling (Fe-staining), firm, compact, wet. Band of grit/small stones at0.05.

-

0.05 - 0.12 Dark brown organic rich silty clay and rootlets.Firm, wet.

0.07-0.08

0.12-0.15 Layer of grit/small stones (0.05m) -0.15-0.19 Dark brown organic rich silt clay becomingslightly crumbly; orange mottling (Fe-staining).

0.15-0.16

0.19-0.26 Larger band of coarser stones (0.01m) insilt/clay matrix

-

0.26-0.39 Dark brown /black organic peaty silt/clay withcommon plant debris.

0.28-0.290.36-0.37

0.39-0.45 Light brown sticky silty clay, orange mottling(Fe)

0.40-0.41

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0.45-0.50 Yellow green sticky silty clay and stones (10mm+) Fe-staining.

-

Table 4: Western trench: sub-sampling for pollen, NPP and lithologicaldescriptions.

4.1.5 Pollen: the sub-samples were processed for pollen using standard procedures(Method B of Berglund & Ralska-Jasiewiczowa 1986) and mounted insilicone oil. The pollen slides were examined using a Leitz Orthomatmicroscope using x400 magnifications routinely. Counting was carried outover two cover slips and continued until a sum of at least one hundred landpollen grains was achieved, or until 10 traverses of the cover slip werereached. Pollen identification was carried out using the standard keys ofFaegri and Iverson (1989) and Moore et al (1991). Microscopic charcoalfragments were quantified, where present, following Peglar (1993). Non-pollen palynomorphs (NPP) (including fungal spores) were identified andquantified, where present. NPP nomenclature followed van Geel (1978) andBlackford et al (in press) and plant nomenclature followed Stace (2010).

4.1.6 Results and Discussion: The raw pollen counts and counts for NPP arepresented on Table 5 (Appendix 1). All sub-samples proved productive forpollen. Rare fungal spores were recorded in the uppermost sub-sample.Palynomorph preservation was generally good but mineral matter obscuredsome grains. Palynomorphs are present in abundance in all sub-samples.Assessment suggests a landscape largely cleared of wood, apart from hazel(Corylus avellana - type), which includes hazel and bog-myrtle (Myrica gale)and heather (Calluna) scrub. Open environments with damp meadows may beinferred from the pollen record.

4.1.7 The deepest sub-sample at 0.40m suggests local vegetation was dominated bywillow (Salix), known to grow in damp, wet areas. Herbs of meadow /hedgerow habitats, such as daisies (Aster-type), dandelions (Taraxacum-type),Devil’s Bit Scabious (Succisa pratensis) and members of the mint family(Mentha-type), are recorded along with ferns indicative of disturbed or roughground. Evidence for clumps of hazel (Corylus) and heather (Calluna) in thevicinity are also noted. Regionally, there is evidence to suggest small stands ofmixed woodland supporting birch (Betula), oak (Quercus), alder (Alnus).Small quantities of microscopic charcoal are present.

4.1.8 The three sub-samples from 0.36m to 0.16m reveal similar pollen assemblagesto each other. Among the tree and shrub taxa, hazel in particular and thenheather, are the most commonly recorded pollen types, suggesting the areasupported a scrub-like vegetation during the time the organic-rich sedimentswere being deposited. The presence of open areas supporting herbcommunities is indicated by common grass (Poaceae) pollen, buttercups(Ranunculaceae) and cinquefoil (Potentilla-type) and in addition to those Taxaoutlined above, suggests possible damp meadow / hedgerow environments.Low counts of possible cereal-type pollen (which could also be a wild grasspollen, Andersen 1979) at 0.36m and the continued presence of low numbersof the disturbance indicator, ribwort plantain (Plantago lanceolata) mayindicate some small-scale cultivation nearby. Pollen evidence also suggests

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regional stands of oak and birch. An increase in the numbers of alder pollenmay reflect increased colonisation of alder trees in wetter areas. Sphagnum(bog-moss) spores are common within these three samples, indicating perhapsslightly more acidic conditions suitable for the growth of mosses. Microscopiccharcoal is present in all sub-samples.

4.1.9 The uppermost sample at 0.08m is similar in pollen composition to thatdescribed for three samples from 0.36m to 0.16m but with evidence of largeropen areas and much reduced hazel and heather coverage. Grass pollen is thedominant herb pollen type recorded but sedge (Cyperaceae) pollen is alsocommonly present, suggesting locally wet areas. The open areas are seen tosupport a greater variety of herb pollen, including meadowsweet (Filipendula),mugwort (Artemisia), and campions (Silene-type), as well as possible cereal-type pollen (which could also be a wild grass pollen, Andersen 1979) and thedisturbance indicator ribwort plantain (Plantago lanceolata). Ribwort plantainis associated with weeds of cultivation and, together with the potential cereal-type record, may suggest that some cultivation was taking place nearby. Smallquantities of microscopic charcoal are present.

4.1.10 Fungal spores are present in the topmost sample at 0.08m. Of significanceamong the relatively low numbers seen during assessment are specimens ofPodospora spp. and Sporomiella spp. Podospora spp. are associated withanimals and man. Podospora spores are considered reliable coprophilousindicators of herbivore dung, especially when in combination with taxa suchas Sporomiella by van Geel et al (2003). The spores of Sporomiella only occurin present day surface samples where grazing herbivores are locally abundant(Davis 1987) and come from obligate coprophilous fungi.

4.1.11 The pollen assessment data support the idea that the older sediments may havebeen deposited within damp, possibly wet environments. The extent to whichmining may have impacted on the vegetational record is difficult to assess.Tin mining utilised both wood and water and may therefore have resulted inboth reduction of tree pollen and in the presence of pollen indicative of wetterenvironments in the pollen profile. It may be that the changes in the pollenassemblage in the samples from 0.36-0.08m suggest the transition to moreopen environments and was coincident with the end of mining and consequentre-adjustment of the vegetation following industrial exploitation.

4.1.12 Recommendations: Detailed analysis is recommended to further refine thepossible environmental changes suggested by the assessment (ie the transitionfrom potential willow wetland to open grassy meadows with heather and hazelscrub environments to a more open, wet and possibly grazed and/or cultivatedlandscape).

4.1.13 Radiocarbon dates would place the vegetational record within anarchaeological context, aiding interpretation. A minimum of two dates isrecommended, one at the base of the organic section and one at the topmostorganic interval. The data could then be integrated with previous work for thearea between Bodmin Moor and Indian Queens (Druce and Verrillforthcoming) and compared with regional pollen data for Bodmin Moor(Gearey 2000a, 2000b). If analysis further supports a transition from wetter

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environments (which may be linked to the cessation of tin mining in the area)to more open land (perhaps used for agricultural purposes), a further date toidentify the age of this change may be important to confirm whether it isrelated to the cessation of tin mining.

4.1.14 A further five sub-samples in addition to those selected at assessment stage (5)would be appropriate for analysis, allowing a 0.04m sampling intervalbetween 0.05m and 0.45m.

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5. DIATOMS AND PHYTOLITHS

5.1 DIATOMS AND PHYTOLITHS

Philip Barker

5.1.1 Methods: Five samples were provided by OA North for diatom analysis.These were prepared using standard procedures. Approximately 1g of materialwas placed in a beaker with 50ml of hydrogen peroxide and heated for 2h tooxidise organic matter. The samples were then filled with deionised water andallowed to settle for 24h before replacing the water. This was repeated threetimes to effectively dilute the residual hydrogen peroxide. Following the finalwash, the samples were dispersed in 200ml of water and the concentration ofsediment in each beaker was assessed. An aliquot of 0.2ml of the suspensionwas taken and pipetted onto a coverslip, this was dispersed in 0.2ml ofdeionised water. The coverslips were dried and permanent slides were madeusing Naphrax high resolution diatom mountant. All the slides were scannedfor diatoms. Diatom remains were found in three samples. Concentrationswere very low in all but one sample and enumeration was made of thoseoccurring in two traverses of each coverslip rather than setting a minimumcount size. This method revealed between 0 and 250 diatoms for each sample.Identifications were made from standard texts, mainly drawn from Krammerand Lange-Bertalot (1986-1991). In addition to diatoms, the remains ofphytoliths were also recorded. A separate aliquot of the sediment was dried toestablish the water content and from this was used to calculate the dry weightof the sediment used in the diatom analysis.

5.1.2 Results and interpretation: The two lowest samples analysed (0.47-0.48m and0.40-0.41m) were entirely devoid of diatoms. Instead, these contained silicateminerals and clay-like complexes. The presence of phytoliths, especially in the0.40-0.41m sample, suggests a soil deposit. These phytoliths were mainly ofthe dumb-bell shape associated with grasses and sedges.

5.1.3 Samples 0.36-0.37m and 0.15-0.16m contained very few diatom remains and afull count was not possible. Those that were present suggest a moistfluctuating habitat, possibly an ephemeral wetland. Some of the diatoms werepartly dissolved but the abundance of phytoliths, which are chemically similar,suggests that diatoms were largely absent. The sample at 0.15-0.16m is veryrich in phytoliths derived from grasses or sedges. These data point to a moisthabitat within a meadow.

5.1.4 The uppermost sample analysed contains a rich diatom flora. More than 28taxa were identified and diversity was very large. The diversity suggests aradiation in the number of niches available to the diatoms. Grass phytolithsare also abundant. The dominant diatom groups were the Fragilaria spp.,indicative of disturbed, turbid environments and aerophilous taxa, such asEunotia. Gomphonema parvulum might indicate some nutrient availability.The presence of Aulacoseira distans suggests an open water pool, as thisdiatom is typically associated with shallow water ponds covered by

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macrophytes. The pH represented by the flora is likely to be weakly acid tocircumneutral. Overall this represents a typical wetland flora with some openwater pools.

Figure 1: the concentrations of diatoms and phytoliths per gram dry weight from GossMoor.

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6. DISCUSSION

6.1 CONCLUSIONS:

6.1.1 The assessment of the palaeo-environmental remains from Goss Moor NNR,Cornwall from the western excavation trench has demonstrated that althoughboth plant and insect remains were present they were poorly preserved. Incontrast, pollen was plentiful and well preserved. Diatoms were absent fromthe two samples taken from the lower clay deposit (0.47-0.48m and 0.40-0.40m) but were identified in the more organic material and in the upper claydeposit (0.02-0.03m), where a rich diatom assemblage was identified.Significant numbers of phytoliths, silicate remains from some plants, wererecorded in all but the lowest sample (0.47-0.48m).

6.1.2 The plant and insect remains are such that little can be inferred about thecondition or development of the local landscape. The paucity of these remainsmay be the result of the high degree of humification of the organic material inthe samples. However, the frequent to common wood fragments do suggest thepresence of some woodland and the insect fragments indicate possibleevidence for grazing animals. Grazing is also suggested by the fungal sporesrecorded in the pollen samples. One insect species is host specific to marsh-marigolds and another to violets suggesting that both these plants were to befound growing nearby.

6.1.3 The pollen, fungal spores, diatoms and plant phytoliths have provided moreevidence of the palaeo-environmental conditions and of the local landscapethan either the plant or insect remains. The assessment of the various strandsof microfossil evidence suggest that for most of the profile, which wassampled by the monolith, the landscape was open with plant communities richin sedges and grasses. The pollen assemblage from the lowest sample (0.46m)differs from those higher up in the profile and suggests that the local landscapewas dominated by willow. The diatom assemblage recorded, at a depth of0.02-0.03m, in the upper yellow, brown grey silty clay (0-0.05m) suggest therewas a typical wetland flora with some open water pools when the deposit waslaid down. Just below this the pollen recorded in dark brown organic-rich siltyclay (at 0.07-0.08m) also points towards locally wet areas.

6.2 POTENTIAL AND RECOMMENDATIONS:

6.2.1 Pollen is the only palaeo-environmental material type where there is anypotential for further analysis. It is recommended that further analysis should beundertaken to further refine the possible environmental changes suggested inthe assessment (ie the transition from potential willow wetland to open grassymeadows with heather and hazel scrub environments and then to a more open,wet and possibly grazed and/or cultivated landscape). These changes may berelated to local mining and quarrying activities.

6.2.2 Scientific dating of the deposits will be used to allow the data to be correlatedwith previous work for the area between Bodmin Moor and Indian Queens(Druce and Verrill forthcoming) and compared with regional pollen data for

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Bodmin Moor (Gearey 2000a, 2000b). If analysis further supports a transitionfrom wetter environments (which may be linked to tin mining in the area) tomore open land (perhaps used for agricultural purposes), a further date toidentify the age of this change may be appropriate.

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BIBLIOGRAPHY

Andersen, STh, 1979 Identification of wild grasses and cereal pollen, Danm GeolUnders, 1978, 69-92

Barber, K. E., and Charman, D. J. (2003). Holocene palaeoclimate records frompeatlands, pp 210-226, In: A. Mackay, R. Battarbee, J. Birks and F. Oldfield, edsGlobal Change in the Holocene, London.

Berglund, BE, and Ralska-Jasiewiczowa, M, 1986 Pollen analysis and pollendiagrams, in BE Berglund (ed), Handbook of Holocene palaeoecology andpalaeohydrology, Chichester, 455-84Blackford, J, J, 1990 Blanket mires and climate change: a palaeoecological testusing peat humification and microfossil analyses. PhD Thesis, Univeristy of Keele,Unpublished.

Blackford, J, J, Innes, J, B, and Clarke, C, (in press) Fungal spores in Quaternarysediments Quaternary Research Association Technical Guide. London.

Brooks, D, and Thomas, KW, 1967 The distribution of pollen grains on microscopeslides. The non randomness of the distribution, Pollen et Spores, 9, 621-9

Cappers, RTJ, Bekker, RM, and Jans, JEA, 2006 Digitale Zadenatlas van Nederland,Groningen

Caseldine, C, and Hatton, J, 1996 Vegetation history of Dartmoor - Holocenedevelopment and the impact of human activity. In: In: Charman, D, J, Newham, R,M, and Croot, D, G, 1996 Devon and East Cornwall Quaternary ResearchAssociation Field Guide pp48-61

Davis, O, K, 1987 Spores of the dung fungus Sporomiella: increased abundance inhistoric sediments and before Pleistocene megafaunal extinction. QuaternaryResearch 28, 290-294.

Druce, D and Verrill, L, forthcoming A30 Bodmin to Indian Queens RoadImprovement scheme: Pollen analysis, in Clark, Paul and Foreman, Stuart, Thearchaeology of the A30 Bodmin to Indian Queens road scheme, Cornish Archaeology

English Heritage, 1991 Management of Archaeological Projects, second edition,London

Faegri, K, and Iversen, J, 1989 Textbook of modern pollen analysis, 4th edn, K Faegri,PE Kaland, and K Krzywinski, Chichester

Geary, B R and Charman, D J 1996 Rough Tor, Bodmin Moor: Testing somearchaeological hypotheses with landscape scale parameters. In: Charman, D J,Newham, R M and Croot, D G 1996 Devon and East Cornwall Quaternary ResearchAssociation Field Guide pp 101-120

Geary, B, R, Charman, D, J, and Kent, M, 2000a Palaeoecological Evidence for thePrehistoric Settlement of Bodmin Moor, Cornwall, southwest England. Part I: The

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Status of Woodland and Early Human Impacts, Journal of Archaeological Science,27, 423-438

Geary, B, R, Charman, D, J, and Kent, M, 2000b Palaeoecological Evidence for thePrehistoric Settlement of Bodmin Moor, Cornwall, southwest England. Part II: LandUse Changes from the Neolithic to the Present, Journal of Archaeological Science,27, 493-508

Jessop, L, 1986 Coleoptera: Scarabaeidae (Handbooks for the Identification ofBritish Insects 5/11) London: Royal Entomological Society of London.

Kenward, H K; Hall, A; and Jones, A K G, 1980. A tested set of techniques for theextraction of plant and animal macrofossils from waterlogged archaeological deposits.Science and Archaeology 22 3–15.

Kenward H K; Engleman C, Robertson A, and Large F, 1985 Rapid Scanning ofUrban Archaeological Deposits for Insect Remains. Circaea 3: 163-172

Krammer, K. & Lange-Bertalot, H. 1986-1991 Bacillariophyceae, Parts 1-4. Volume2 of "Süsswasserflora von Mitteleuropa", edited by Ettl, H, et al Gustav FischerVerlag, Stuttgart, Germany.

Lucht, W H, 1987 Die Käfer Mitteleuropas (Katalog). Krefeld: Goecke and Evers.

Mighall, T, and Chambers, F, 1993 The environmental impct of prehistoric mining atCopa Hill, Cwmystwyth, Wales. The Holocene, 3, 3, pp 260-264

Moore, PD, Webb, JA, and Collinson, ME, 1991 Pollen analysis, Oxford

Peglar, SM, 1993 The mid Holocene elm decline at Diss Mere, Norfolk, UK: a yearby year pollen stratigraphy from annual laminations, Holocene, 3.1, 1-13

OAN 2011 Goss Moor National Nature Reserve Palaeo-environmental AssessmentProject Design.

Stace, C, 2010 The new flora of the British Isles, third edition, Cambridge

Stockmarr, J, 1972 Tablets with spores used in absolute pollen analysis, Pollen etSpores, 13, 615-21

van Geel, B, 1978 A palaeoecological study of Holocene peat bogs sections inGermany and the Netherlands. Review Palaeobotany and Palynology 25, 1-120.

van Geel, B, Buurmann, J, Brinkkemper, O, Schelvis, J, Aptroot, A, van Reenen, Gand Hakbijl, T, 2003 Environmental reconstruction of a Roman Period settlementsite in Uitgeest (The Netherlands), with special reference to coprophilous fungi.Journal of Archaeological Science, 30, 873-883.

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APPENDIX 1: TABLES

Sampleno

Sampledescription

Flot vol(ml)

Flot description Plant remains(seeds)

Potential

1 Brown humiclayer abovepeat

200 Amorphous organic (4),insects (1), stones (3)

- None

2 Black graveloverlying peat

200 Stones (4) - None

3 Peat: 0-0.05m 200 Amorphous organic (4),wood fragments (3),roots (3), insect eggs (4),stones (4), charcoal (1)

- None

na Peat 0.05-0.06m

150 Amorphous organic (4),wood fragments (3),roots (3), insect eggs (4),stones (3), charcoal (1)

- None

4 Peat: 0.06-0.1m

200 Amorphous organic (4),earthworm eggs (1),charcoal (1)

WPR (1) Rumexacetosella

None

5 Peat: 0.1-0.15m

200 Amorphous organic (4),roots (3), insect eggs (3),stones (2), charcoal (1)

WPR (2) Carex None

6 Peat: 0.15-0.20m

200 Amorphous organic (4),wood fragments (2),roots (4), stones (3),sand (2)

- None

7 Peat 0.20-0.28m (abovegravel)

200 Amorphous organic (4),roots (3), stones (3),charcoal (1)

- None

na Bulk samplefrom upper halfof peat.Contains blackgravel andsmallinclusions.Above linearfeature

200 Amorphous organic (4),wood fragments (2),roots (3), insect eggs (3),stones (3), charcoal (1)

WPR (1)indeterminate

None

na Bulk samplefrom lower halfof peat

200 Amorphous organic (4),wood fragments (2),roots (3), insect eggs (1),earthworm eggs (1),stones (3), charcoal (1)

- None

na Lower half oflinear feature

200 Stones (4) - None

Table 1 Assessment results of the plant remains from Goss Moor, Cornwall.Material scored on a scale of 1-4 where 1 is rare (up to 5 items) and 4 isabundant (>100 items). WPR = waterlogged plant remains

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Sample no. Ecologicalcodes

Top ofpeat

Brownlayer

Top of peatblack/browngravel

Top ofpeatdark

gravel

Top ofpeat

0.6-0.10m

Peat 0.10-0.15

Abovegravel peat0.20-0.22m

Host plant

Sample volume (L.) 2 2 2 4 2Sample weight (Kg.) 2.5 4.6 1.6 5 1.6

COLEOPTERACarabidae

Notiophilus spp. - + - - - -Clivina fossor (L.) - - - - - +

Dyschirius globosus(Hbst.)

+ ++ - +++ - -

Trechus spp. + - - - - -Bembidion spp. + - - + - -

Pterostichus spp. - - - ++ - -

HydrophilidaeCercyon spp. + - - + - -

Cryptopleurumminutum (F.)

df - - - + - -

Chaetarthriaseminulum (Hbst.)

a + - - ++ - -

StaphylinidaeOxytelus rugosus (F.) + - - - - -

Oxytelus spp. + - - + - -Stenus spp. + - - - - -

Lathrobium spp. oa + - - - - +Xantholinus spp. + - - + - -Philonthus spp. + - - - - -

Aleocharinidae Genus& spp. Indet.

- + + - - -

ScarabaeidaeAphodius spp. df +++ + + ++ + +

ChyrsomelidaePlateumaris sericea

(L.)ws + - - - - - Usually on Carex spp.

(sedges)Donacia/ Plateumaris

spp.ws + - - - - -

Hydrothassa marginella(L.)

ws - + - - - - Often Caltha palustrisL. (Marsh marigold)

CurculionidaeOrobitis cyaneus (L.) p - - - + - - Viola spp. (violets)

Table 2: Assessment results for the insect remains from Goss Moor NNR,Cornwall

Samples that produced no insect remains

Peat top 0.05m, peat 0.15-0.20m, Bottom of peat, bottom of feature.

Key to ecological coding

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a= aquatic water beetlesws = water side taxa often associated with emergent vegetationdf = taxa often associated with dungp= taxa associated with grassland and open areasl= taxa associated with treesm= taxa associated with moorland

key to numbers of individuals+ = 1-2 individuals++ = 2-5 individuals+++ = 5-10 individuals

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Western TrenchPreservation Good Good Good Good Good

Potential Good Good Good Good GoodDepth (m) 0.08 0.16 0.28 0.36 0.40

Trees and shrubsAlnus Alder 7 8 13 12 2Betula Birch 2 5 4 5 2Ulmus Elm 1 1

Quercus Oak 4 3 2Fraxinus Ash 1Corylus Hazel 23 46 64 65 10

Salix Willow 1 57Ilex Holly 1

Calluna Heather 8 15 26 13 11Crops

Cereal-type 1 1Herbs

Artemisia Mugwort 1Aster-type Daisy-type 1 2 1 1 4

Centaurea nigra Knapweed 1Cyperaceae Sedges 13 2 1 1Fabaceae Pea family 1

Filipendula Meadowsweet 1Hypericum-type St. John’s Wort 1

Mentha-type Mints 1Plantago lanceolata Ribwort Plantain 3 1 1 2

Poaceae Grass family 39 20 24 21 3Potentilla-type Cinquefoil 4 6 2Ranunculaceae Buttercup family 1 1 1

Rubiaceae Bedstraw family 1 1Silene-type Pinks 2

Succisa pratensis Devil’s Bit Scabious 1 1 1 1 5Taraxacum-type Dandelions 5 1 4 1 1Unknown herbs 5 4 4 0 5

Total land pollen 124 114 152 127 101Number of traverses 1 1 1 1 3

Ferns and mossesPolypodium Polypodies 2 8 5 2 10Pteridium Bracken 1 3 2 3

Pteropsida (monolete) Fern spores (monolete) 1 1 2 1Pteridophyta (undiff.) Fern spores (trilete) 3

Sphagnum Bog moss spores 1 4 8 10Indeterminate pollen

Broken grains 4 2 1 2 7Concealed grains 8 3 7Corroded grainsCrumpled grains 2 4 8 11 20

AquaticsPotamogeton Pondweeds 1 1

Microscopic charcoal + ++ ++ ++ +Fungal spores

Type 18 1 1Podospora 1

Sporomiella 1Undiff. Fungal spores 2 1

Table 5: Western trench: pollen and fungal spores, raw counts.

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0.02-0.03m

0.15-0.16m

0.36-0.37m

0.40-0.41m

0.47-0.48m

0.02-0.03m(%)

Phytoliths 73 103 95 12 3Aulacoseira distans 7 2.8Brachysira serians 8 3.2Cymbellaamphicephala

2 0.8

Cymbella silesiaca 3 4 1.2Diatoma mesodon 1 0.4Eunotia curvata 1 0.4Eunotia minima 14 5.6Eunotia pectinalis 27 2 10.8Eunotia spp 2 0.8Fragilaria capucina 15 6Fragilaria construens 54 21.6Fragilaria virescens 9 3.6Frustulia vulgare 6 2.4Gomphonemaolivaceum

1 0

Gomphonemaparvulum

33 2 13.2

Hantzschia amphioxys 1 0.4Meridion circulare 3 1.2Naviculacryptocephala

6 2.4

Navicula lanceolata 7 2.8Navicula mutica 2 0.8Navicula spp. 7 2.8Nitzschia sp 5 2Pinnularia borealis 4 1 1.6Pinnulariamicrostauron

5 2

Pinnularia viridis 8 3 3.2Synedra acus 4 1.6Synedra ulna 8 3.2Tabellaria floculosa 8 3.2Total diatomscounted

250 9 4 0 0

Diatoms /g (dry) 337,126,001

14,441,043

3,330,282

0 0

Phytoliths/g 98,440,792

165,269,718

79,094,186

15,973,813

1,512,452

Table 6: Assessment results for the diatoms and phytoliths from Goss Moor, Cornwall

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APPENDIX 2: PROJECT DESIGN

EXECUTIVE SUMMARY

Oxford Archaeology North (OA North) received a brief from Natural England todesign a costed project design for the palaeo-environmental assessment of samplestaken during two excavations on the Goss Moor National Nature Reserve, Cornwall.The brief stated that the samples were to be assessed for pollen, plant macrofossilsand insect remains but if the assessment of other remains was thought to be desirablea case should be made for their inclusion. OA North has suggested that fungal sporesand diatoms should also be assessed for the following reasons:

• fungal spores may help in our understanding of the nature of the localenvironment, animal and anthropogenic activity for example some fungal sporesare associated with damaged trees. There is no additional cost implication inundertaking this assessment.

• diatoms are habitat specific and are therefore good indicators of suchcharacteristics as minerals, salinity and water quality which may be ofconsiderable importance from a site that is known to have been influenced by tinand gravel extraction. There is an additional cost implication in undertaking thisassessment.

STAFFING

The pollen, fungal spores and plant macrofossils will be assessed in house by the OANorth environmental team. The insects and diatoms will be assessed by externalspecialists.

1. INTRODUCTION

1.1 PROJECT BACKGROUND

1.1.1 Natural England (hereafter the ‘client’) has requested that Oxford ArchaeologyNorth (OA North) submit a costed Project Design describing a Palaeo-environmental Assessment of environmental samples taken during twoexcavations ahead of a project to divert the River Fal from an over-deepenedchannel, which was created in the 1970s to prevent the threat of pollutionepisodes from the China Clay industry upstream. The two excavation trencheswere at both ends of this channel.

1.1.2 The lower, western trench exposed a sequence of stratified deposits of mainlygravels and clays with a more organic looking layer towards the base. Thedeposits are thought to have been lain down naturally and are described as

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possibly water-lain in a flood plain. A single archaeological feature wasidentified in this trench.

1.1.3 The eastern trench and the deposits are described as being disturbed possiblyas the result of tin-streaming and more recently by gravel extraction. GossMoor was extensively disturbed by tin and gravel extraction in the 19th and20th centuries although this may have commenced in the Bronze Age.

1.1.4 Both bulk and monolith environmental samples were taken from the westerntrench. The bulk samples were taken during machine excavation, whichcurtailed the available time for sampling. A preliminary assessment needs to beundertaken on these samples.

1.2 SITE BACKGROUND

1.2.1 Goss Moor NNR, Cornwall is situated in a broad relatively flat, valley basin whichforms the headwaters of the River Fal. The extensive mining of alluvial tin depositssince the Bronze Age, and in the more recent past gravel extraction has resulted inthe formation of wetland habitats. No industrial activity has taken place since the1960s.

1.3 OXFORD ARCHAEOLOGY NORTH

1.3.1 The company, both as Oxford Archaeology North, and under the former guise ofLancaster University Archaeological Unit (LUAU), has considerable experience ofsites of all periods, having undertaken a great number of small and large scaleprojects throughout Northern England during the past 25 years and latterly inSouthern England. Evaluations, assessments, watching briefs and excavations havetaken place within the planning process, to fulfil the requirements of clients andplanning authorities, to very rigorous timetables.

1.3.2 OA North has the professional expertise and resources to undertake the projectdetailed below to a high level of quality and efficiency. OA North is an Institute ofField Archaeologists (IFA) registered organisation, registration number 17, and allits members of staff operate subject to the IFA Code of Conduct.

2 OBJECTIVES

2.1 The following programme has been designed following the brief (TRURI2011:19) received by OA North from Natural England.

• Stage 1: Assessment of pollen, fungal spores and diatoms

• Stage 2: Assessment of plant macrofossils

• Stage 3: Assessment of insect remains

• Stage 4: Reporting

• Analysis and dating.

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2.2 Stage 1: Assessment of pollen, fungal spores and diatoms: small sub-samples will be taken from the monolith sample and processed for pollen,fungal spores and diatoms.

2.3 The prepared samples will be assessed by the individual specialists. Thepollen and fungal spores will be assessed in house and the diatom will besubmitted to the relevant specialist.

2.4 Stage 2: Assessment of plant macrofossils: a one litre sub-sample will betaken from each bulk sample will be processed and assessed for plantmacrofossils. The plant macrofossils will be assessed in house

2.5 Stage 3: Assessment of insect remains: : the remaining volume from eachbulk sample will be processed and assessed for insect remains. The insectremains will be assessed by the relevant specialist.

2.6 Stage 4: Reporting: A written report will be produced giving the results ofthe assessment, an outline of the archaeological implications of the combinedwork and an indication if any Stage 4 work is warranted.

2.7 Stage 5: Analysis and dating: This stage will comprise full analysis ofpollen, fungal spores, plant macrofossils, insects and diatoms and it will besupported by a programme of scientific dating. An account of successiveenvironments and an outline of archaeological implications will be given. Ifthe results are of sufficient merit they may be published in an appropriateacademic journal.

2.8 Report and archive: a written report will be produced at Stage 3 to assess thesignificance of the data generated by the programme within a local andregional context. It will present the results of the assessments from eachstage. The data will be entered into OASIS, the Online Access to the Index ofarchaeological investigations.

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3 METHOD STATEMENT

3.1 Palaeo-environmental Assessment

3.1.1 Stage 1: Pollen, fungal spores and diatoms: Samples for pollen and fungalspores will be processed in house by the OA North environmental team butsamples for diatom assessment will be submitted to the relevant specialist.

3.1.2 The pollen in the sediment will be assessed to help understand the nature andprocesses of accumulation of the waterlogged deposits and also the localenvironment. The pollen assessment method to be used is in the followingparagraphs.

3.1.3 The monolith sample will be cleaned and recorded on pro-forma sheetsfollowing the standard guidelines for Geoarchaeology (English Heritage2004). A description of the deposits using standard quaternary (LateDevensian and Holocene) terminology (colour texture, compaction andinclusions) will be compiled.

3.1.4 Five small sub-samples will be taken from the monolith for the assessment ofpollen and fungal spores. A further five samples will be taken for theassessment of diatoms.

3.1.5 Pollen and fungal spores: five sub-samples, 10-20ml in volume, willprepared for pollen analysis using a standard chemical procedure (method Bof Berglund & Ralska – Jasiewiczowa (1986), using HCl, NaOH, sieving,HF, and Erdtman’s acetolysis, to remove carbonates, humic acids, particles >170 microns, silicates, and cellulose, respectively. The samples will bestained with safranin, dehydrated in tertiary butyl alcohol, and the residuesmounted in 2000 cs silicone oil. Slides will be examined at a magnification of400x (1000x for critical examination) by ten equally-spaced traverses or atotal 100 land pollen and spores if fewer transects are needed across twoslides to reduce the possible effects of differential dispersal on the slide(Brooks & Thomas, 1967). Lycopodium tablets (Stockmarr, 1971) will beadded to a known volume of sediment at the beginning of the preparation sothat pollen concentrations could be calculated. Pollen identification will bemade using the keys of Moore et al. (1991), Faegri & Iversen (1989), and asmall modern pollen reference collection. Andersen (1979) will be followedfor identification of cereal-type grains. Indeterminable grains will also berecorded as an indication of the state of the pollen preservation. Plantnomenclature will follow Stace, 1997. Fungal spore identification andinterpretation will follow van Geel (1978) and Blackford, J.J. (et al. 2010) (inpress).

3.1.6 The data will be presented in tables as either percentage values or actualnumbers of pollen grains and spores. The interpretation of the data may helpin our understanding of the nature in which the waterlogged depositsaccumulated and also of the local and regional environment.

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3.1.7 Fungal spores: the data will be presented in tables as either percentagevalues or actual numbers of fungal spores. The interpretation of the data mayhelp in our understanding of the nature of the local environment, animal andanthropogenic activity for example some fungal spores are associated withdamaged trees (Innes et al 2006) .

3.1.8 Diatoms: five small sub-samples of the sediment samples will be submittedto the relevant specialist (Dr Philip Barker), who will prepare 10ml samplesfollowing the standard hydrogen peroxide and hydrochloric acid procedure(Batterbbee 1986). The sediments will be processed and assessed for thepresence and absence of diatoms. If present the diatoms will be identifiedand quantified.

3.1.9 Diatoms are freshwater or marine algae with a silica frustule or chamber,which is resistant to decay. They are habitat specific and are therefore a goodindicators of such characteristics as minerals, salinity and water quality(English Heritage, 2002). As it is recorded that Goss Moor has beeninfluenced by tin and gravel extraction information about the water qualityand mineral content of the deposits will be a very important indicator ofbiological conditions.

3.1.10 Stage 2: Assessment of plant macrofossils: the bulk samples will beprocessed and assessed for the presence or absence of plant macrofossils bythe OA North in house environmental team. The brief states that the depositsare thought to have been water-lain and therefore it is anticipated that theplant remains will have been preserved by water logging and the processingmethodology is based on this assumption. A one litre sample of each bulksample will be washed through 250 micron mesh, retained wet and examinedunder a low powered binocular microscope. If present the plant macrofossilswill be identified, where possible, quantified and the potential for furtheranalysis will be recorded.

3.1.11 Waterlogged plant remains are good indicators of the local flora. They can beused as proxy indicators of climate change and hydrological conditions(Barber and Charman, 2003).

3.1.12 Stage 3: Assessment of insect remains: The remainder of the bulk sampleswill be submitted to the relevant specialist, who would process them byparaffin flotation techniques and assess the flots for the presence of insectremains. If these are present they are invaluable to our understanding of thenature of the deposits, possible urban habitation conditions and the economyof the sites.

3.1.13 Stage 4: Reporting: The data from the pollen, fungal spores, diatoms, plantmacrofossil and insect assessment will be presented in a written report withan outline of the archaeological implications. Proposals will be made forfurther analysis if warranted and the methodology for this analysis will alsobe included.

3.1.14 Stage 5: analysis and dating: if the environmental assessment demonstratesthe potential for further research of the pollen, fungal spores, diatoms, plant

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macrofossils and insects, a programme of full analysis for all or some of thesamples will be recommended. The details of the methodology will beoutlined in the Stage 3 report. This programme of analysis will supported bya programme of scientific dating and the advice of the Scottish UniversitiesEnvironmental Research Centre will be sought.

3.2 REPORT

3.2.1 Report: three bound and one unbound copy of the final report will besubmitted to the client within two months following the commissioning of theproject. The report will include:

• a site location plan related to the national grid;

• a front cover to include the planning application number and the NGR;

• the dates on which each phase of the programme of work was undertaken;

• a concise, non-technical summary of the results;

• an explanation to any agreed variations to the brief, including anyjustification for any analyses not undertaken;

• a description of the methodology employed, work undertaken and resultsobtained;

• a description of the pollen, fungal spores, plant macrofossil and insectassessments undertaken and the results obtained;

• a summary of the impact of the development on any archaeologicalremains and, where possible, a model of potential archaeological depositswithin as-yet unexplored areas of the development site;

• a copy of this project design, and indications of any agreed departurefrom that design;

• Recommendations for further works

• the report will also include a complete bibliography of sources fromwhich data has been derived.

3.2.2 This report will be in the same basic format as this project design; a copy ofthe report can be provided on CD, if required.

3.2.3 Confidentiality: all internal reports to the client are designed as documentsfor the specific use of the client, for the particular purpose as defined in theproject brief and project design, and should be treated as such. They are notsuitable for publication as academic documents or otherwise withoutamendment or revision.

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3.2.4 Archive: the results of all environmental archaeology work carried out willform the basis for a full archive to professional standards, in accordance withcurrent standard guidelines (English Heritage 1991; 2002; 2004). The projectarchive will include summary processing and analysis of all features, finds, orpalaeo-environmental data recovered during fieldwork, which will becatalogued by context.

4. HEALTH AND SAFETY

4.1 OA North provides a Health and Safety Statement for all projects andmaintains a Unit Safety policy. All site procedures are in accordance with theguidance set out in the Health and Safety Manual compiled by the StandingConference of Archaeological Unit Managers (1997). A written riskassessment will be undertaken in advance of project commencement andcopies will be made available on request to all interested parties.

5 PROJECT MONITORING

5.1 Whilst the work is undertaken for the client, J Joy Ede the SW HistoricEnvironment Specialist Archaeologist, for Natural England will be kept fullyinformed of the work and its results. Any proposed changes to the WrittenScheme of Investigation will be agreed with Joy Ede in consultation with theclient.

6 TIMING, STAFFING AND AVAILABILITY

6.1 Timing: The final report will be submitted to the client within two monthsfollowing the commissioning of the project by the client .

6.2 Staffing: All staff participating in the project should be suitably qualified andappropriate experience in this type of project. If OA North are successful theproject will be under the direct management of Murray Cook MA, MIFA,FSA Scot, OA North Post-Excavation Manager.

6.3 All environmental sub-sampling and assessment will be undertaken under theauspices of Elizabeth Huckerby BA, MSc, MIFA (OA North EnvironmentalManager) who has experience of palaeoenvironmental work in the North WestEngland having worked on the North West Wetlands Survey and the UplandPeat Project both English Heritage funded Projects and who heads a team ofenvironmental archaeologists. Elizabeth has experience of sites, in Southernand Eastern Britain, France and Ireland. Denise Druce BA, PhD who hasconsiderable experience of working in the North West England on the Upland

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Peat Project and many other projects in North West England. She also hasexperience of working on the Severn Estuary, Cornwall, Central and SouthernWales and Southern and Eastern Britain. Denise has previously analysed thepollen from the lower palaeochannel sequence identified in the stream valleysouth-west of Belowda Lane on Goss Moor (Druce and Verrill forthcoming).Mairead Rutherford BA, MSc, an experienced pollen analyst, has workedon sites throughout the British Isles, including several sites in West and NorthWest Scotland, the Pennines and North Cumbria will assess the pollen andfungal spores. Elizabeth Huckerby, an experienced waterlogged plantremains and pollen specialist will assess the waterlogged plant remains.Curricula Vitae are to be found in Appendix 1.

6.4 The insects will be assessed by either David Smith, MA(CANTAB), MA,PhD, FRES Birmingham University or Enid Allison, B Sc, D Phil,Canterbury Archaeological Trust depending on their availability. Both arevery experienced insect specialists. The diatoms will be assessed by PhilipBarker at the University of Lancaster, a very experienced diatom specialist.Curricula Vitae are available on request.

6.5 Availability: OA North has availability to undertake and complete this workwithin two months following the commissioning of the project by the client.

7 INSURANCE

7.1 The successful contractor shall provide professional indemnity cover to avalue of £2,000,000; proof of which to be supplied.

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8 REFERENCES

Andersen, S,Th, (1979). Identification of wild grasses and cereal pollen. Danm GeolUnders, 1978, 69-92.

Barber, K. E., and Charman, D. J. (2003). Holocene palaeoclimate records frompeatlands. In Global Change in the Holocene (A. Mackay, R. Battarbee, J. Birks andF. Oldfield, Eds.), pp. 210–226. Arnold, London.

Battarbee, R,W, 1986 Diatom analysis in BE Berglund (ed), Handbook of HolocenePalaeoecology and Palaeohydrology. Wiley: Chichester Berglund, 527-70

Berglund, B,E, & Ralska-Jasiewiczowa, M, (1986). Pollen analysis and pollendiagrams. In Berglund, B.E. (ed) Handbook of Holocene Palaeoecology andPalaeohydrology. Wiley: Chichester, pp 455-484.

Blackford, J, J, Innes, J, B, and Clarke, C, (in press) Fungal spores in Quaternarysediments. Quaternary Research Association Technical Guide London.

Brooks, D, & Thomas, K,W, (1967) The distribution of pollen grains on microscopeslides. The non randomness of the distribution. Pollen Spores, 9, 621-629.

Druce, D and Verrill, V, A30 Bodmin to Indian Queens Road Improvement scheme:Pollen analysis, in Clark, Paul and Foreman, Stuart, forthcoming The archaeology ofthe A30 Bodmin to Indian Queens road scheme, Cornish Archaeology

English Heritage, 1991 Management of Archaeological Projects, second edition,London

English Heritage, 2002, Environmental Archaeology, London

English Heritage, 2004, Geoarchaeology;, Using earth sciences to understand thearchaeological record, London

Faegri, K, & Iversen, J, (1989) Textbook of modern pollen analysis. 4th. Ed. Faegri,K., Kaland, P.E. & Krzywinski, K. (eds.). Wiley: Chichester, 328 pp.

Grimm, E,C, 1991 TiliaGraph 2.0.b.5. Illinois State Museum, Research andCollections Center, Springfield, Illinois.

Innes, J, B, Blackford J, J, and Chambers, F, 2006 Kretzschmaria deusta and theNorthwest European mid-Holocene Ulmus decline at Moel y Gerddi North Wales UKPalynology 30 121-132

Moore, P,D, Webb, J,A, & Collinson, M,E, 1991 Pollen analysis. BlackwellScientific Publications: Oxford, 216 pp.

Oxford Archaeology 2005, Environmental Sampling Guidelines, 2nd ed.

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SCAUM (Standing Conference of Archaeological Unit Managers), 1997 Health andSafety Manual, Poole

Stace, C, 1997 New Flora of the British Isles. Cambridge University Press:Cambridge, 1130 pp

Stockmarr, J, 1972 Tablets with spores used in absolute pollen analysis. Pollen etSpores 13, 615-621.

UKIC, 1990 Guidelines for the Preparation of Archives for Long-Term Storage,London

UKIC, 1998 First Aid for Finds, London

van Geel, B, 1978 A palaeoecological study of Holocene peat bog sections inGermany and the Netherlands, based on the analysis of pollen, spores and macro-andmicroscopic remains of fungi, algae, cormophytes and animals Review ofPalaeobotany and Palynology 25 1-120